Separation analysis of dry high intensity induced roll magnetic separator for concentration of hematite fines

In this study, a three level Box–Behnken factorial design combined with response surface methodology was used for modeling and optimization of process parameters of induced roll dry high intensity magnetic separator. The influence of magnetic field intensity, roll speed and feed rate was analyzed for the separation of hematite minerals. Second-order response functions were produced for the grade and recovery of the hematite minerals in the magnetic fraction. Taking advantage of the quadratic programming, optimized levels of the process variables have been determined as optimum levels to achieve the maximum grade of 51.2% Fe, and maximum level of recovery was 97.8% Fe whereas minimum grade of 23.9% SiO2 in the magnetic product was predicted. Further optimization was carried out by targeting the Fe (%) content and recovery of the magnetic product of above 50%. The influence of the process variables of the induced roll high intensity magnetic separator on grade and recovery of the hematite mineral in the magnetic fraction were presented as 3D response surface graphs.